(1)The Secretary of State may—
(a)vary a designation under section 257, but not so as to vary the cut-off date, or
(b)revoke such a designation.
(2)The Secretary of State may by a variation of the designation extend the period referred to in section 257(3)(c) (period within which assistance must be applied for) whether or not it has expired.
(3)The variation or revocation of a designation does not affect the operation of the provisions of this Part in relation to a dwelling if, before the variation or revocation comes into operation, the dwelling is a defective dwelling by virtue of the designation in question and an application for assistance under this Part has been made.
(4)Notice of the variation or revocation of a designation shall be published in the Edinburgh Gazette.